The present invention relates to corrugated containers in general, and in particular to an improved one piece interlocking outfold container which has plural thickness front, back and side walls for increased stacking strength.
Cardboard or corrugated boxes or containers are used to package various goods. Conventionally, such a container comprises a rectangular cardboard sleeve which is slit along its corners at each of its ends to define four flaps at each end. To form the container bottom wall, a pair of opposed flaps at one end of the sleeve is folded inwardly of the sleeve, the other pair of flaps is folded inwardly of the sleeve and across the one pair, and the flaps are secured in folded position by adhesive, tape or any other suitable means. Goods may then be placed in the container through the opposite open end, whereafter the end is closed by folding and sealing the flaps thereat to provide a closed cover on the container.
A difficulty encountered with conventional containers is that the front, back and side walls thereof comprise only a single thickness of cardboard, i.e., the walls of the container are the sides of the sleeve. In consequence, the containers have limited stacking strength, and when heavily loaded and stacked one on top of the other they tend to collapse. To give the containers greater stacking strength, it is known to insert a separate corrugated cardboard liner or sleeve around the goods therein. The sleeve has the same height as the container, and gives the container greater vertical ridigity. However, it is expensive and inconvenient to store a supply of and use separate tubular liners.
Another disadvantage of such containers is that to facilitate shipping and storage, the rectangular cardboard sleeves are folded flat during shipment and storage and until such time as the container is to be formed and used. Consequently, the user must provide his own means for securing the flaps closed at opposite ends of the sleeve to form the container bottom and cover.